Understanding Trends in Reaction Rates in Heterogeneous and Electro-Catalysis
Understanding and predicting reaction rates from first-principles calculations are critical to designing materials and micro-environments for energy storage applications.
In the first part of this talk, I will discuss how descriptor-based approaches, such as linear scaling relations, have led to a systematic understanding of trends in activity in heterogeneous and electro-catalysis. While such an approach has been successful in understanding catalytic reactions, there are instances where linear scaling does not hold. To rationalize these observations, I will present a model for chemisorption of small molecule adsorbates by combining a modified form of the Newns–Anderson hybridization energy with an effective orthogonalization term. This model removes the need for linearity in scaling relations, allowing for a general and quick estimation of reaction rates.
In the second part of this talk, I will present applications specific to electrochemical CO2 reduction. By combining the framework of scaling relations with a handful of computed reaction rates, I will discuss the likely reaction mechanism for CO2 electro-reduction to CO. We show that our computations are in alignment with available pH-dependent experimental activity measurements.
I will conclude by discussing the need for data-driven approaches to studying reaction rates, particularly for studying passivation films in Li-ion batteries.
Sudarshan Vijay is a post-doc in the group of Prof. Kristin Persson at UC Berkeley, where he works on developing data-driven models to predict properties of electrochemical reactions. He received his PhD in Applied Physics from the Technical University of Denmark in 2022, working in the group of Prof. Jens K. Nørskov, where he developed an electronic structure understanding of adsorption with applications in heterogeneous and electro-catalysis. During his PhD, he was awarded support from the Otto Mønsteds Foundation to visit the group of Prof. Nicola Marzari at École Polytechnique Fédérale de Lausanne, where worked on developing methodology to compute formation energies of charged defects in 2D materials. Prior to his PhD, he conducted research at the Department of Chemistry at Carnegie Mellon University and obtained his Bachelors in Chemical Engineering from Birla Institute of Technology and Science, Pilani, India. His research interests include surface catalysis, electrochemistry and chemical kinetics.
[1]: Vijay S, Kastlunger G, Chan K, Nørskov JK. Limits to scaling relations between adsorption energies? Journal of Chemical Physics (2022)
[2]: Vijay S, Ju W, Brückner S, Tsang SC, Strasser P, Chan K. Unified mechanistic understanding of CO2 reduction to CO on transition metal and single atom catalysts. Nature Catalysis. (2021)